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323 Uppsatser om Nitrogen removal - Sida 15 av 22

Uppvärmning och miljöpåverkan : -en jämförelse mellan fjärrvärme och bergvärme i villa

Many of todays studies show that district heating is one of the betteralternatives as heating source because of its low environmental load.The energy source is often leftovers from other processes producing energy or waste, like garbage or chips.Electricity in combination with geothermal heating is another heating system that has increased sharply during the last years, and also this system decreases the discharges that have negative affectson the environment compared to several other heating methods.This report aims to, concentrated towards these two different heating systems, estimate the amounts of discharges they indirect cause and how the environment is affected.We have calculated the mean value for discharges of carbon dioxide, nitrogen oxide, sulphur oxide and dust generated from electrical power used in Sweden.Through interviews and research we have gained data for the same substances that district heating based on combustion of garbage and biofuel generates.We have also in cooperation with a housing company chosen a building we see representative for many of the new single-family houses built in Sweden today.Based on its shape and appearance we theoretically created three alternatives of the same house, each of them with climate screens different from each other.Together with the amounts of discharged environmental affecting substances, these houses were the base for our calculations and studies when investigating the different heating sources environmental effect.The results have thereafter been analyzed and discussed from different angles..

Police Science - expansionen av ett kunskapsfält : En studie om vetenskapligt gränsdragningsarbete i 1930-talets Chicago

In 1929, the Scientific Crime Detection Laboratory was established in Chicago?the first of its kind in the United States. The purpose was to engage in practical use of scientific methods in the detection of crime. In 1930, the institute published its own periodical called The American Journal of Police Science. Applying the theory of boundary-work, this essay analyses how the novelty institute argued its legitimacy as a scientific establishment through the expansion of Police Science as a collective field of knowledge.

Inventering och karakterisering av brännbart avfall i
Norrköpingsregionen

The purpose of this study has been to make an inventory of combustible waste in the region around Norrköping and to investigate the composition of domestic waste, industrial waste and two different types of sludge. The work was performed at the request of Norrköping Miljö & Energi, due to the planning of an incineration plant. The inventory of the waste was performed through inspection of environmental impact reports, from waste disposal plants in a number of local government areas in the region. The quantities were also compared to another inventory, carried out in a different way. The characterisation of the wastes was compared to the fuel specification determined by Norrköping Miljö & Energi.

Har en gemensam valuta resulterat i en minskad prisspridning? : En jämförande studie på priskonvergens inom euroländer i förhållande till övriga EU länder

In 1993 the internal market within the European Union was formed and ensured free movement of goods, services, capital and people. This led to the removal of trade barriers between members of the European Union. When opening up for competition, price differences between countries decreased and more jobs were created. A single currency was introduced by eleven countries in 1999 with the goal of reducing transaction costs, eliminating exchange rate risk and to further simplify trade. In 2001 Greece joined the collaboration and introduced the euro.

Klimatsimulering av ett kontorsrum : Hur de termiska stigkrafterna påverkar ventilationseffektiviteten

AbstractIn urban societies people spend more and more time indoors, which put great demands on the indoor environment. If the ventilation is to manage the removal of unwanted substances in the indoor air, a good mixing of the air is required. The question arises that, whether the buoyancy forces will counteract a good mixing of the indoor air or not?This report aims to clear up the difficulties whether you need to consider the buoyancy forces or not, when adjusting a ventilation unit. For studying the indoor mixing of the air a two dimensional model is constructed in COMSOL Multiphysics.

Inokulering med två hjorttryfflar på arginingödslade täckrotsplantor i Gideå plantskola :

The effect of inoculation on containerized pine and spruce seedlings in a nursery with two ectomycorrhizal fungi was investigated in regard to the development of mycorrhiza and plant growth. The fungi were Elaphomyces muricatus and Elaphomyces granulates and the inoculated seedlings were compared to an uninoculated control. These seedlings were all fertilized with arginine. Five mycorrhiza species were found after DNA sequencing of the mycorrhizal root tips with different found morphotypes on seedlings from all treatments. Thelephora terrestris was the type which had the greatest distribution on pine seedlings and Tylospora asterophora was found at big extent on spruce seedlings. The inoculated species was not found, if it was due to the species hadn?t colonized the roots or if the DNA sequencing failed we can only speculate about.

Dödsrikets livshistorier : Benkemiska isotopanalyser på artikulerade och disartikulerade individer i Frälsegårdens gånggrift

The aim in this thesis is to use carbon, nitrogen and sulfur isotope analysis on teeth and bone to track diet and mobility of the population as well as the individual level from the articulated and disarticulated individuals from the passage grave Frälsegården, situated in Gökhem parish in the region of Falbygden, western Sweden.50 human samples were analyzed from tooth, mandibula and femur, together with 11 faunal samples from different bone elements of local wild and domestic animals.The results fall well in line with earlier stable isotope work done on passage grave individuals from Falbygden in stable isotopes: A homogenous group with a diet which was clearly terrestrial and lived on a pretty high trophic level. It also seems that the analyzed individuals deliberately focused their food intake to the cultural and natural, megalith and limestone landscape of Falbygden, and not to its surroundings, even if the passage grave is situated in the outermost areas of the region.A small study compares the sulfur results to with earlier work done on strontium isotopes. The results show that the different methods might provide a deeper understanding in the interpretation of the methods, and therefore suggesting that further work should be done to compare the methods..

Biologiska behandlingsmetoder för rening av rejektvatten från biogasproduktion

In this literature review the characteristics of two free-floating macrophytes, water hyacinth   (Eichhornia crassipes) and duckweed (Lemna sp.), and two microalgae, Chlorella and Scenedesmus, have been examined regarding their suitability as efficient nutrient removers in the treatment of wastewater with high levels of nutrients and suspended solids from a biogas plant in Loudden. The needs required for the plants to be able to grow in wastewater and the amounts of biomass they can produce have also been studied. The results show that Chlorella is capable of a very high uptake of nutrients in photobioreactors with high nutrient loadings. With an ammonia uptake maximum value at 10900mg/m2/d Chlorella outshines the other organisms in this study. The test organism that performed the closest to Chlorella in terms of nitrogen uptake was water hyacinth with an uptake about 1602mg/m2/d.

Miljöarbete inom den civila luftfarten

The main environmental problem for aviation is the great amount of exhaust gases, mainly nitrogen oxides, carbon monoxide, carbon dioxide and hydrocarbons - mostly "greenhouse gases" leading to climate changes. I decided to sort out what is being done to decrease these problems and what regulations there are concerning air pollution by the means of searching the internet and using publications from aviation authorities for current figures. I chose to scrutinize authorities on political, authority and company level, resulting in summarizing the work of UN and EU respectively, ICAO (International Civil Aviation Organization), JAA (Joint Aviation Authorities) and LFV (Swedish Civil Aviation Authority), and finally SAS, representing the airline companies. Conclusion that I have drawn are thatthere are regulations for air pollution, written down in ICAO's Annex 16, that are to be followed. Secondly, LFV are environmentally controlling their nineteen airports and since economy is an important reason for not giving priority to environmental issues in aviation emission charge and noise charge are added to the landing fees.

Otitis externa hos hund ? förebyggande åtgärder och råd till djurägare

Otitis externa is a disease regularly encountered in veterinary practice. It is estimated to be the most common disease in the external ear canal of dogs and treatment is often delayed due to unfortunate pet owner ignorance. Owners tend to assume that scratching of the ears and head shaking are natural behaviours in their dog and may be neglecting the problem unknowing of how severe it actually is. A literature study has been carried out to examine the causes of otitis externa in order to present a collection of measures that can be used in the treatment and prevention of the disease. In turn these measures can be advised to the dog owner and used in the home environment to make the best qualifications for healthy ears in the dog. The causes of otitis externa have been divided into predisposing, primary, secondary and perperuating causes.

Biochar as soil amendment in flow-through planters - for increased treatment of zinc roof runoff

In times of increased flooding, enhanced by climate change, polluted stormwater poses an increased threat to the environment through contaminated water entering waterways. Bioretention utilizes natural processes in soil and vegetation to treat pollutants and combat this threat. Biochar produced through pyrolysis, has a high cation exchange capacity (CEC) and could therefore increase treatment in bioretention systems. This research applies a literature review, interview, and a model to explore the benefits and disadvantages of biochar in order to specify a soil-mix through an understanding of the production process and preferred application rate. High purification through CEC, increased water holding capacity, and carbon sequestration being the benefits discussed.

Ammoniakförluster vid flytgödselhantering : myllning och surgörning som metoder för att minska avgång vid spridning

The ammonia emissions are an environmental issue since they contribute to eutrophication. By far the largest source of ammonia emissions is manure from agriculture and should therefore be reduced. Loss of ammonia is not only negative for the environment but also to the farmer who loses nitrogen that could have been used by the crop. The focus of this study has been emissions from spreading slurry where the loss can vary widely depending on slurry-, soil-, and weather conditions. There are mainly two different ways to reduce the emissions. One is to inject or mix the slurry into the ground to avoid air contact. The other way is to use acid to reduce the pH in the slurry to a level between 5 and 6 where the equilibrium is so strongly pushed to NH4+ that hardly any NH3 can be lost.

Rening av avloppsvatten med anaerob membranbioreaktor och omvänd osmos

This master's theses was carried out on assignment from Stockholm Vatten AB as a part of a project developing new waste water treatment techniques. The goal of the theisis has been to evaluate an anaerobic membrane bioreactor for treatment of waste water from Hammarby Sjöstad. The bioreactor has not been heated and the main interest has been to study the gas production, power consumption and the reduction of organic matter and nutrients.The system has been completed with a reverse osmosis unit and a total of four batch runs have been made with good results. The use of reverse osmosis allows nutrient in the waste water to be reintroduced into circulation as the reverse osmosis concentrate can be used as crop nutrient.The membrane unit is of VSEP ("Vibratory Shear Enhanced Processing") type and an extensive membrane test has been conducted. This so called L-test helped determine the most suitable type of membrane for the system to allow a higher ±ux and thus lower power consumption.

Bakterietillväxt i strömedel till mjölkkor

The resting area is the most important place in the barn for the dairy cow, sometimes called the heart of the free stall system. Inadequate design of the lying area, and lack of or poor quality of bedding materials may reduce the hygiene of the stall. Poor management regarding the cleanliness of the resting area may lead to poor animal hygiene and increased bacterial growth. This in turn will lead to increased risk for environmental mastitis as well as impairing milk quality through contamination with spores. In this literature study the most commonly used bedding materials; straw, sawdust, wood shavings, clean sand, recycled sand, peat and recycled manure solids, are compared to one another with regards to their ability to resist bacterial growth. Effects of adding hydrated lime to bedding materials have also been studied. Most bacteria need humidity and prefer a quite high water activity to be able to grow.

Tillsats av biokol till en svensk sandjord : effekter på lustgasavgång, kväveretention och andel vattenfyllda porer

In a column experiment the effect of three different biochars on nitrous gas emissions, nitrogenretention and water filled pore space (WFPS) were studied in a Swedish sandy soil, classified as aCryopsamment. Ammonium retention was positively correlated, while KCl-extractable ammoniumwas negatively correlated, with the specific area of the biochars. The question was raised whether thenegative correlation between extractable ammonium and biochar specific area reflects the amount ofammonium present in the soil or its extractability from the biochar, and whether methods forextracting soil mineral nitrogen, like KCl-extractions, have to be modified for application on biocharamended soils. There was a tendency of increased nitrate retention and KCl-extractable nitrate withbiochar and KCl-extractable nitrate was positively correlated with the specific area of the biochar. pHwas higher for all biochars compared with control, although the differences were not significant, andWFPS was lowered by biochar addition, significantly in one case.

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